The present invention relates to cellular insulation panels. It has one of its most important applications as an insulating panel for covering windows or other openings. These panels most commonly comprise a plurality of tubular sections adhesively secured together. The panel can be oriented so that the tubular sections form a horizontally contractible and expandable panel which extends vertically, such as when covering a doorway or other similar openings. The panel more commonly is used with an orientation where the tubular sections form a vertically collapsible and expandable panel extending horizontally, such as when covering a window.
In window covering, the panel is mounted upon a headrail with pull cords extending down through holes in the panel to a bottom rail secured to the bottom of the panel. In some panel designs, each tubular section is a strip of usually thermoplastic woven or unwoven sheet material folded into an open-top tube. Each tube-forming strip is initially completely separate from the other tubular strips forming the panel and is laminated to the adjacent strips of the panel by bands of adhesive. The folds of each tubular section are usually sharp or set so that they appear as lines or bands which improve the aesthetic appearance of the panel. Such a panel is disclosed in Dutch Published Application No. 6706563 published Nov. 11, 1968 to Landa. In this Dutch publication, the cells have a rectangular, hexagonal or a pointed oval shape, depending on the width of the adhesive bands and the degree of expansion of the cells. If the adjacent tubular sections are secured together over wide securement bands and are fully expanded, the cells have a rectangular shape, as is shown in U.S. Pat. No. 4,019,554 granted on Apr. 26, 1977 to Rasmussen.
In another form of cellular panel construction, a pair of zig-zag shaped sheets of material are placed into confronting relation and secured together at the abutting fold points, to form diamond-shaped cells. This panel construction is disclosed in U.S. Pat. No. 2,201,356 granted Nov. 21, 1938 to Terrell.
The rear side of all these cellular panels, which interrupt the passage of light when covering a window, preferably have a color to reflect light. The front side of the panels, which face into the room involved, desirably have an appearance from a strictly aesthetic standpoint. In the panel design where each tubular section is made of a separate sheet of material folded into a tube, one half of the sheet may be printed or embossed before it is folded into a tubular shape, so that the portion of each sheet which faces the inside of the room is provided with the desired aesthetic appearance. The other half of each sheet, which faces towards the window has color to reflect light. If the initial sheet of material is already of a desired light color to reflect light, it can remain without any added coloring. If the sheet forming each tubular strip is made of an expensive material to give the front side of the panel an attractive appearance, the high cost of the portion of the same sheet which is to face the window is an undesired expense.
The panel design having diamond shaped cells, described previously, made from a pair of separate, confronting zig-zag shaped sheets does not have this problem as only the front sheet must be made of the more expensive material. However, this type of panel is less attractive to some purchasers than the panel having pointed oval, hexagonal or rectangular cells. Also, the method required for fabricating the panel made from zig-zag shaped sheets is less efficient and more difficult to control than the method used to make a panel of separate folded strips of material adhesively secured together.
The preferred cellular panel constructed and manufactured in accordance with the present invention overcomes these disadvantages. The panel can have cells of any desired shape, and can be made by a very efficient stacking process. In addition, only the front side of the panel requires a more expensive material, satisfying the aesthetic objectives of purchasers, and thus, the rear side can be made of a less expensive material, which is only required to reflect light, and aid in forming an insulating panel.
Many of the present features of the invention are applicable to another type of panel to be referred to as a light-controlling cellular panel, which is used to cover primarily windows. In this panel, the front vertical side of each horizontally extending cell is made of a sheer material, preferably of one mesh size, and the rear vertical side of each cell is made of a sheer material preferably of a different mesh size or mesh shape, to avoid a Moire effect. When the panel is in its light-passing state, the upper or lower horizontal wall of each cell is a horizontal opaque wall which, most desirably, is wider than the height of the cell. When one of the vertical sides of the panel is shifted upward or downward with respect to the other vertical side of the panel, the opaque walls are pivoted into substantially vertical positions where they completely overlap, to obstruct the passage of light through the panel.
Most of the methods previously used to fabricate this type of light-controlling panel did not permit the ready manufacture of any desired width of the panel. The commercial forms of this panel have been usually constructed from two horizontally spaced confronting unfolded vertical sheets of sheer material, which respectively formed the complete front and rear sides of the panel. Opaque strips of material are adhesively secured at spaced vertical points between the front and rear sheer sheets of the panel. The cells of this panel have a rectangular shape. As will later be described, the present invention provides a very efficient and effective means for manufacturing a panel having a similar appearance to this panel, but is constructed much differently. The present invention is made from a multiplicity of separate identical strips of material of any desired length, cut from a continuous web and laminated by an efficient strip stacking process where the panel can have any desired length. The panel can then be made into any width using a highly efficient stacking process.